The liturgical life of the Catholic Church revolves around the Eucharistic sacrifice and the sacraments. There are seven sacraments in the Church: Baptism, Confirmation, Eucharist, Penance, Anointing of the Sick, Matrimony, and Holy Orders.
The purpose of the sacraments is to make people holy, to build up the body of Christ, and finally, to worship God; but being signs, they also have a teaching function. They not only presuppose faith, but by words and object, they also nourish, strengthen, and express it; that is why they are called "sacraments of faith." The sacraments impart grace, but, in addition, the very act of celebrating them disposes the faithful most effectively to receive this grace in a fruitful manner, to worship God rightly, and to practice charity.
Worship is integral to our lives as Christians. When we engage in the prayer and ritual of the Church, we are formed as Church. Our sacramental rites are of primary importance while we are gathered.
The history of human salvation is the history of the way God came to men. The first step on this way was the bridging of the gulf separating God and man in the person of the one Mediator Jesus Christ and by his work of redemption. By means of his Church Christ makes his grace available to all. Only in this application of redemption to mankind is the redemptive action of Christ completed. The doctrine of the sacraments is the doctrine of the second part of God's way of salvation to us. It deals with the holy signs which Christ instituted as the vehicles of his grace.
The great mystery of the union in Christ of a human nature with the second Person of the Godhead is that the human actions and sufferings of Christ are divine actions and sufferings. The sacraments are a living continuation of this mystery. There are earthly, external signs here which, of themselves, could never acquire any supernatural significance, but the signs of the sacraments have been made by Christ into vehicles of his grace. They effect in men the grace for which Christ made them the sign.
So there are two fundamental ideas which constantly recur in the Church's teaching, on the sacraments. First there is the Church's concern for these instituted by Christ, their number, and their proper preservation and administration; then the grace which Christ has for all time linked with these signs and which is communicated by them.
The second is the effect of the sacraments. They are the signs of Christ's work; the effectiveness of Christ's continuing work in his Church cannot be dependent on man's inadequacy. A sacrament, administered properly in the way established by Christ and with the proper intention, gives the grace it signifies. It is effective not by reason of the power of intercession of priestly prayer nor on account of the worthiness of the recipient, but solely by the power of Christ. The power of Christ lives in the sacraments. The effect of the sacrament is independent of the sinfulness or unworthiness of the minister. The Church has never tolerated any subjective qualification of the objective effectiveness of the sacraments ex opere operato. This would ultimately be to conceive the way of salvation as being man's way to God and not God's way to man.